Let's get a big welcome to our colleague and dear friend David Muir. He officially -- yes. Hey. There was no applause sign, David. That was from the heart. I he takes over as the anchor of "World news tonight." Beginning of a new and exciting ear R you know how we feel about you. I've known you and I've known of your passion and your devotion. This is something that you've thought about as a small child. Yeah, you and I have talked about how important family is especially when you're a small child growing up. I was the 12-year-old with a dream and wrote to the local newscaster and waited for that letter to come back and finally did. He said, you know, there's always room for the right person, it could be you. And a week or two later I'm in the TV station carrying the tripods and the scripts and for years on my summer breaks they would let me come in and measure how much I had grown from summer to summer on the newsroom wall with a bright red face but now I look back and so grateful to everyone who gave me a shot. You are the right person for being in that chair. You know that and it's not just about being in the chair. You're going to get out. That's what you are known for and you're going to continue to do that. I think the viewers at home who watch our reporting would say what happened to this guy if I wasn't still out in the field doing these stories and we're just back from the Syrian border because there are so many children who have left Syria with their families from middle class family, their parents were theechers, lawyers and now they're living in Lebanon and the children are the ones who actually support the entire family. I want everyone to get their firsthand look at this. Let's do it. Reporter: There is no school bus waiting, instead a truck of the children soon spilling over. And we board the truck with them. We're not going to school. We're headed to the fields. She points out the way. This way? This way. This way? Reporter: The children, their tiny hands holding on many from middle class families in Syria, now they are the ones who support their families. You're going to work on the potatoes. Potatoes. Yes. You never stop to think about that. The children supporting their families and they hire only the children because the adults would have to pay more and learn in the field even the little boys make more than the little girls and say the boys are stronger. Oh, come on. We are shining a spotlight on this tonight and hopefully the world will remember there are children right now, you know, hundreds of thousands of them working, instead of going to school sflul's be all around the world and right here at home made in America. Made in America. That's right. Had say series and this is really the power of where I think the opening news is headed. Viewers can now reach out and say when are you coming to our hometown. We discovered the one thing that will save jobs in America and be out there this week. Spotlighting another company, another family determined to make it here. A family business from new England and they said we had offers to go to China, Mexico and they stayed here and now there's a resurgence and creating jobs and we'll show you what it is. Always look forward to those reports. I hope you'll still make time for us on this little bitty show called "Good morning America." Please make time for us. You know how happy we are for you and just all the best. All the very best. Everyone at home should know, robin, you have been cheering me on every step of the way. Amen brother. "World news tonight with David Muir." You can see it tonight and every night right here an ABC.

This transcript has been automatically generated and may not be 100% accurate.

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